Curious as to what your plans are when the trailers are released and the movie itself. Are you going to do sub-forums for "Discuss Watchmen Teasers/Trailers" and "Discuss the Movie?"
I don't think that the teasers and trailers will be enough to sustain their own sub-forum. When the teaser is released, it'll get its own thread for discussion, and then it'll become another bit of evidence for the users to bring up in other discussions about the movie. Repeat for the subsequent trailers.
I actually like AYB's idea, though I would change it a bit: On 3.6.9, maybe we could retitle the current movie sub-forum as "Movie Speculation" or something, and we could keep it open for discussion about the impending DVD release and what it should be like. Then, of course, we could open up a new sub-forum for discussion on the final movie.
It's important to understand that restructuring the forum is a big undertaking. A lot of thought needs to be put into it.